The Environmental Protection Agency (referred to hereafter as ``EPA'' or ``the Agency'') proposed a new compliance assurance program (referred to as ``CAP 2000'') on July 23, 1998. This action adopts revised emissions compliance procedures for new light-duty vehicles and light-duty trucks contained in the NPRM. CAP 2000 simplifies and streamlines the current procedures manufacturers must follow to obtain pre-production emission certification of new motor vehicles. The new certification program provides the same environmental benefits as the current procedures while significantly reducing the certification cost for manufacturers, and giving manufacturers more control of production timing. EPA is also adopting a requirement that manufacturers test in- use motor vehicles to monitor compliance with emission standards. Manufacturers will test samples of in-use vehicles when they are approximately one and four years old. These test data will be used to improve the process which predicts in-use compliance and will determine the need for further action by the Agency or the manufacturer to address any in-use emission compliance problems. CAP 2000 will be implemented beginning with model year (MY) 2001 vehicles. Manufacturers are allowed to voluntarily opt-in to the CAP 2000 procedures beginning with the 2000 model year. EPA estimates that overall, manufacturers will save about $55 million dollars a year as a result of today's final rule.